Understanding Obesity in Cats

A fat cat has the image of opulent luxury, contentment and happiness. But in reality, fat cats face serious health risks, lower quality of life and even depression.

There are many reasons why pets (and people) become obese, but they really fall under two main categories: our pets eat too much and do not exercise enough. As long as a cat is no more than a pound above normal for an average-sized cat, there may be no cause for concern. But if the extra weight amounts to more than 15 percent over the ideal body weight, the cat is clinically obese. Now there are serious health risks to consider.

The greater an animal’s caloric intake over the course of his life, the shorter that life span will be. Folks talk about vitamins and minerals, amino acids and supplements that might keep our pets healthy but caloric intake alone is the single biggest determinant of an animal’s (or person’s) life span. It’s a simple formula: more calories = fewer years.

By itself, obesity carries with it its own set of physical problems that can contribute to a pet’s early demise. Fat cats have an increased risk of cardiovascular disease, respiratory disease, liver disease, diabetes, orthopedic problems and even neurological problems. As our cats’ protectors, we should take obesity seriously and feed and exercise them sensibly.

Reducing Caloric Intake in Cats

One way is simply to reduce the amount of food we are feeding our cats subtly. “Crash diets” are never appropriate. Drastic reduction of food intake is:

a) Potentially dangerous
b) Inhumane
c) Contributing factor to the “yo-yo syndrome” of sudden weight loss followed by rapid weight gain (when the original feeding regimen is reinstituted)

The yo-yo syndrome is the reason so many people fail to lose weight when they put themselves on a diet. If any animal (including humans) does not get enough food for awhile his body goes into crash-dive starvation mode, in which any calories stumbled across are used with maximum efficiency. If feeding meals infrequently is not the answer, and eating whenever you want doesn’t work, there must be a happy medium – and there is. Eat enough to lose weight at a frequency that doesn’t make your body act as if it’s facing starvation. For cats, twice daily feeding of reasonable amounts of high fiber low fat cat food is a good approach. Also, treats should be suitably formulated, small and strictly rationed. But even with such measures, some cats still don’t lose weight.

This is when you should enlist your veterinarian’s help. First, he or she may check for medical conditions, such as hypothyroidism, that may stack the deck against the cat. Medical problems should be treated first. If medical causes of obesity are not involved, a supervised calorie-restricted diet is probably in order. Such diets are proprietary these days like Hill’s Science Diet® weight reduction (r/d) and Purina® OM® overweight management diet. Purina supplies vets with a computer program so they can calculate exact daily rations for their patients. Simply plug in the weight of the cat and the desired rate of weight loss and the computer tells how much of the ration to feed.

The program limits the cat’s weight loss to no more than 4 percent per week to prevent problems associated with overly rapid loss of weight. The essence of weight-loss diets is to provide a proper balance of nutrients while meeting the special dietary needs of the overweight patient. Weight reduction diets tend to be low fat and high fiber. This makes the food restriction less psychologically stressful by helping the cat to feel “full.”

Psychological Causes of Obesity in Cats

Just about any psychologically stressful situation can lead an anxious cat to engage in what is called a “displacement behavior.” Displacement behaviors include eating, drinking, grooming, chasing, running or walking, and so on. All are naturally endowed behaviors but can be performed during stressful moments to reduce the impact of stress or conflict.

If the conflict is prolonged, the displacement behavior can become ingrained, almost as if the neural pathways involved have become well worn and facilitated. At this stage the displacement behavior has reached the proportions of an obsessive-compulsive disorder (OCD) and will be performed out of the context of direct or obvious stress. If the OCD takes the form of excess eating, the cat will gain weight. OCDs are a sad behavioral statement testifying to earlier or existing chronic inescapable or unmanageable conflict.

In treatment, the first rule is to identify and eliminate all existing causes of conflict and to make sure that the cat has a happy and healthy lifestyle, replete with opportunities for exercise and entertainment. But even if these conditions are met, many cats continue on their relentless tasks of compulsive eating, self-licking, tail chasing and the like. In such cases, fluoxetine (Prozac®), paroxetine (Paxil®), fluvoxamine (Luvox®) or other anti-obsessional drugs may be helpful. If the correct diagnosis is made and the correct treatment is applied in the correct manner, the weight can fall off a compulsive feline overeater.

Exercise in Cats

Though not a good primary strategy for weight loss, exercise can help. Theoretically, cats and people have to exercise quite a lot to lose even a little weight, yet exercise does seem to help. It provides an outlet for pent-up energy that might otherwise transmute into anxious eating behavior. Another more biochemical reason is that exercise generates increased amounts of the neurotransmitter serotonin in the brain. Serotonin has two effects that might be relevant: First, it helps to prevent depression and has anti-obsessive properties. Second, it reduces appetite. Both are desirable.

When Weight Loss is Too Rapid in Cats

The big bugaboo when it comes to dieting cats is so-called hepatic lipidosis. In this condition, fatty deposits of “lipids” accumulate within the liver and impair its function. It is not quite clear whether altered metabolism caused by rapid weight loss or the stress of under eating (or both) causes the problem but either way it happens. Most veterinarians are so worried about this syndrome that they are really reluctant to put cats on diets. Actually hepatic lipidosis, as serious as it is, is not that common. It is rarely if ever seen in cats over 18 pounds in weight. In dieted lighter cats it is the exception rather than the rule.

To be safe, “easy does it” is the name of the game. It is probably safe for cats to lose up to 3 to 4 percent of their body weight per week. The Purina® OM weight loss program limits weight loss to 4 percent per week. The problem then becomes not hepatic failure but failure of owners (and their cats) to follow the dietary restriction. For example, laboratory cats slated to lose 2 percent of body weight per week lose exactly that. Home living cats often only achieve one quarter of this weight loss, a mere 0.5 percent weight loss. Some owners cave in to their cats’ demands; other cats are clever in finding forbidden foods.

Healthy weight loss can enrich your cat’s life. Even in the early stage of a carefully gauged and monitored diet, overweight cats begin to display changes in temperament and behavior that indicate that they are feeling much better. They play more, sleep less and become more active. It’s as if they’re saying, “Thank you for rescuing me from my eating obsession.”